Ignition distributors

ABSTRACT

A method of assembling an ignition distributor of the kind including a base plate which is secured to the casing of the distributor and a timing plate mounted for angular movement on the base plate, the timing plate carrying in use the contact breaker assembly of the distributor, including the steps of engaging the annular timing plate with the base plate. The base plate and the timing plate include mating surfaces which locate the timing plates for angular movement on the base plate when the timing plate and base plate are interengaged. Three tags or ears formed on the base plate are then deformed to overlie the surface of the timing plate remote from the base plate, the ears being such that any one of the ears is on the opposite side of a diameter of the plate from the remaining ears. The ears are bent to a position such that a predetermined clearance exists between the lower surfaces of the ears and the upper surface of the timing plate, so that the timing plate is held against disengagement from the base plate in an axial direction, but there is a predetermined amount of clearance between the ears and the timing plate, so that the timing plate is capable of small movements in an axial direction. In a first alternative the ears are deformed to the desired position prior to engagement of the timing plate with the base plate, and the timing plate is formed with slots through which the ears pass when the timing plate is engaged with the base plate. In a further modification the timing plate includes a plurality of projections onto which the ears are bent, the projections defining the extent of the clearance, and in a still further alternative the timing plate has projections which engage the base plate, and the base plate has apertures into which the projections can locate upon angular movement of the timing plate relative to the base plate. In this embodiment, the ears are deformed into engagement with the timing plate while the projections engage the surface of the base plate, and the timing plate is then rotated so that the projections locate in the apertures, and the predetermined clearance exists between the timing plate and the ears.

United States Patent Cooksey Sept. 5, 1972 [54] IGNITION DISTRIBUTORS William Harold Cooksey, 5 Penryn Close, Park Hall, Wals all, England [22] Filed: Aug. 12, 1970 [21] Appl. No.: 63,248

[72] Inventor:

[30] Foreign Application Priority Data Aug. 12, 1969 Great Britain ..40,l87/69 52 U.S .Cl. ..29/598,200/19R 51 Int. Cl. ..H02k 15/02 [58] Field of Search ..29/437, 438, 598; 200/19 R, ZOO/l9 A, 19 B, 19 L, 19 E, 19 DR, 19 DC, 19 M, l9TF, l9 WG;3l0/42 Primary Examiner-Robert L. Spicer, Jr. Attorney-Holman & Stern [57] ABSTRACT A method of assembling an ignition distributor of the kind including a base plate which is secured to the casing of the distributor and a timing plate mounted for angular movement on the base plate, the timing I 7 plate carrying in use the contact breaker assembly of the distributor, including the steps of engaging the annular timing plate with'the base plate. The base plate and the timing plate include mating surfaces which locate the timing plates for angular movement on the base plate when the timing plate and base plate are interengaged. Three tags or ears formed on the base plate are then deformed to overlie the surface of the timing plate remote from the base plate, the ears being such that any one of the ears is on the opposite side of a diameter of the plate from the remaining ears. The ears are bent to a position such that a predetermined clearance exists between the lower surfaces of the ears and the upper surface of the timing plate, so that the timing plate is held against disengagement from the base plate in an axial direction, but there is a predetermined amount of clearance between the ears and the timing plate, so that the timing plate is capable of small movements in an axial direction. In a first alternative the ears are deformed to the desired position prior to engagement of the timing plate with the base plate, and the timing plate is formed with slots through which the ears pass when the timing plate is engaged with the base plate. In a further modification the timing plate includes a plurality of projections onto which the ears are bent, the projections defining the extent of the clearance, and in a still further alternative the timing plate has projections which engage the base plate, and the base plate has apertures into which the projections can locate upon angular movement of the timing plate relative to the base plate. In this embodiment, the ears are deformed into engagement with the timing plate while the projections engage the surface of the base plate, and the timing plate is then rotated so that the ro'ections locate in the a rtures, and he predetermi ed pe t plate and the ears.

10 Claims, 9 Drawing Figures clearance exists between the timing "mgm n 5|972 f 3888392 I SHEETIUFS ATTORNEYS PATENTEDsEP 5 1972 saw 3 or 3 ATTORNEYS IGNITION DISTRIBUTORS This invention relates to a method of assembling ignition distributors of the kind including a base plate which is secured to the casing of the distributor and a timing plate mounted for angular movement on the base plate, the timing plate carrying the contact breaker assembly of the distributor.

A method according to a first aspect of the invention includes the steps of, engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate, and deforming three ears formed on a first plate of the pair of plates defined by the timing plate and the base plate to overlie the surface of the second plate of said pair of plates remote from the first plate, said ears being disposed on said first plate so that any one of the ears is on the opposite side of a diameter of the plate from the remaining ears, and the ears being so deformed that a predetermined clearance exists between said surface of the second plate and the ears.

A method according to a second aspect of the invention includes the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three projections on a first plate of the pair of plates defined by the timing plate and the base plate engage the surface of the second plate, said projections being disposed on the first plate in such a manner that any one of the projections is on the opposite side of a diameter of the plate from the remaining projections, deforming three ears formed either on the second plate or the first plate to engage the surface of the first plate or the second plate remote from the plate having the ears, the ears being so disposed on the second plate or on the first plate that any one of the ears is on the opposite side of a diameter of the plate from the remaining ears, and rotating the first and second plates relative to one another so that the three projections enter respective apertures in the second plate, the dimensions of the apertures in the second plate being such that the first plate can move angularly relative to the second plate, and the first plate being movable axially relative to the second plate through a distance equal to the height of the projections.

A method according to a third aspect of the invention includes the steps engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three projections on a first plate of the pair of plates defined by the timing plate and the base plate project from the surface of the first plate, remote from the second plate, said projections being disposed on the first plate in such a manner that any one of the projections is on the opposite side of a diameter of the plate from the remaining projections, deforming three cars formed on the second plate to engage the surfaces of the three projections respectively and rotating the first and second plates relative to one another to displace the three projections angularly from the three ears so that the first plate is capable of movement axially relative to the second plate through a distance equal to the height of the projections.

A method according to a fourth example of the invention comprises, starting with a first annular plate having integral therewith three inwardly directed ears, the ears being spaced from the surface of the plate by a predetermined distance and being arranged so that anyone of the ears is on the opposite side of a diameter of the plate from the remaining ears, engaging with said first plate a second plate having three inwardly directed slots, said ears passing through said slots and mating parts on said first and second plates interengaging to mount the plates for relative angular movement, and, rotating the second plate relative to the first plate to displace the slots from their respective ears so that the ears retain the plates interengaged in an axial direction, said predetermined distance being such that a predetermined clearance exists between the ears and the surface of the second plate remote from the first plate, one of said first and second plates constituting a base plate while the other plate constitutes a timing plate and said one plate being arranged to be fixed to the casing of an ignition distributor while said other plate is arranged to support a contact breaker assembly.

In the accompanying drawings FIGS. 1 and 2 illustrate one stage in the manufacture of an ignition distributor in accordance with one example of the invention,

FIGS. 3 and 4 illustrate one stage in the manufacture of an ignition distributor in accordance with a second example of the invention,

FIGS. 5 and 6 illustrate one stage in the manufacture of an ignition distributor in accordance with a third example of the invention,

FIGS. 7 and 8 illustrate one stage in the manufacture of an ignition distributor in accordance with a fourth example of the invention and FIG. 9 is a diagrammatic sectional view of an ignition distributor manufactured in accordance with any one of the above examples of the invention.

Referring first to FIGS. 1 and 2 of the drawings, the distributor includes an annular base plate 11 including a pair of diametrically opposite, integral tags 12 by means of which the base plate 11 is mounted within the casing of an ignition distributor. The wall of the central hole 13 in the plate 11 is extended at right angles to the plane of the plate 1 1 to define a short cylindrical spigot 21 and upstanding from the periphery of the plate 11 are three deformable tags 15. The tags 15 are integral with the plate 11, and for convenience are equi-angularly spaced around the periphery of the plate 11. An annular timing plate 16 which will carry the contact breaker assembly of the distributor is engaged with the plate 11, the spigot 21 of the plate 11 entering the central hole in the plate 16 and serving to locate the plate 16 for angular movement relative to the plate 11 about the axis of the spigot 14. The tags 15 are then deformed to extend over the plate 16 to retain the plate 16 in an axial direction. In order that the plate 16 can move angularly with a minimum of drag from the tags 15, the tags 15 are deformed so that there is a predetermined clearance between the tags 18 and the upper surface of the plate 16. Means not shown is provided for limiting the angular movement of the plate 16 relative to the plate 11.

In a modification shown in FIGS. 7 and 8 the plate 1 l assembly of the plate 11 and the plate 16, the plate 16 is formed with three equi-angularly spaced slots 15a through which the deformed tags 15 pass during assembly, and after assembly the plate 16 is rotated relative to the plate 11 to displace the slots 15a from the tags 15 so as to minimize the risk of subsequent disengagement of the plates 1 1 16.

In the example shown in FIGS. 3 and 4 the distributor once again includes an annular base plate 11 including a pair of diametrically opposite, integral tags 12 by means of which the base plate 11 is mounted within the casing of an ignition distributor. The wall of the central hole 13 in the plate 11 is again extended at right angles to the plane of the plate 1 1 to define a short cylindrical spigot 21 and upstanding from the periphery of the plate 11 are three deformable tags 15. Again the tags 15 are integral with the plate 11, and for convenience are equi-angularly spaced around the periphery of the plate 11. The annular timing plate 16 which will carry the contact breaker assembly of the distributor is engaged with the plate 11, the spigot 21 of the plate 11 entering the central hole 17 in the plate 16 and serving to locate the plate 16 for angular movement relative to the plate 11 about the axis of the spigot 14. The plate 16 is stamped from sheet metal, and during the stamping operation three equi-angularly spaced depressions are formed adjacent the periphery of the plate 16. The three depressions are formed in the plate 16 by half shearing the plate 16, and so three projections 18 are defined on the underside of the plate 16. The plate 16 is engaged with the plate 11 with the projections 18 engaged with the upper surface of the plate 11. The tags 15 are of greater width than the depressions associated with the projections 18, and when the plate 16 is engaged with the plate 11 the tags 15 are deformed to engage the upper surface of the plate 16.

Adjacent each of the tags 15 the plate 11 is formed with a slot 19 the arcuate length of the slot 19 being greater than the width of the projections 18. After deformation of the tags 15 the plate 16 is rotated relative to the plate 11 so that the projections 18 engage in the slots 19. Thus, the plate 16 is located for angular movement relative to the plate 11 by the spigot 21, the degree of angular movement being limited by engagement of the projections 18 with the ends of their respective slots 19. Moreover the plate 16 is held against disengagement from the plate 11 in an axial direction by the tags 15, but has a predetermined permitted degree of free axial movement relative to the plate 11, the permitted axial movement of the plate 16 being equal in distance to the height of the projections 18. The height of the projections 18 is so chosen that the degree of clearance which exists between the plate 11 and the plate 16 is the minimum clearance which is required to prevent appreciable drag between the plate 11 and the plate 16 when the plate 16 is moved angularly with respect to the plate 1 1.

In an alternative construction the tags 15 are formed on the plate 16 rather than the plate 11, and the tags 15 are such that when bent they extend radially inwardly beyond the inner edges of the slots 19 to prevent disengagement of the plates 16,11.

It will be appreciated that since the projections 18 on the plate 16 are formed by a stamping process then numerous plates can be produced having their projections 18 all within predetermined tolerance ranges.

In a modification FIGS. 5 and 6 the slots 19 are dispensed with. The plate 16 is engaged with the plate 11 with the projections 18 upstanding from the surface of the plate 16, remote from the plate 11 and the tags 15 are bent to engage the tops of the projections 18. Thus upon rotation of the plate 16 relative to the plate 11 the projections 18 are displaced angularly from the tags 15 thereby providing the required degree of free axial movement of the plate 16 relative to the plate 11 equal to the height of the projections 18.

An assembly defined by the plate 16 and the plate 11 as described above is inserted into the casing 22 of an ignition distributor, (FIG. 9), and the assembly is secured to the casing 22 of the distributor by inserting screws through holes in the lugs 12, the screws engaging the casing 22. The cam shaft 23 of the distributor extends upwardly through the spigot 14, and the contact breaker assembly of the distributor is mounted on the surface of the plate 16 remote from the plate 1 l. A vacuum advance capsule (not shown secured to the casing of the ignition distributor is connected to the plate 16 by means of a connecting rod, and the plate 16 is moved relative to the casing of the ignition distributor upon operation of the vacuum capsule, the plate 16 moving about the axis of the spigot 14. The cam shaft 23 of the distributor is co-axial with the spigot 14, and so movement of the timing plate 16 under the action of the vacuum capsule adjusts the ignition timing of the distributor without altering the contact gap of the contact breaker assembly, since the contact breaker assembly is moved in an arc of a circle having its center on the axis of the cam shaft. The plate 16 is provided with nylon bearing pads which engage the plate 11 and which further reduce the drag between the plates l1, 16. The casing 22 is closed, in use, by an insulating cap 24.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A method of assembling an ignition distributor of the kind specified including the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate, and deforming three ears formed on a first plate of the pair of plates defined by the timing plate and the base plate to overlie the surface of the second plate of said pair of plates remote from the first plate, said ears being disposed on said first plate so that any one of the ears is on the opposite side of a diameter of the plate from the remaining ears, said step of deforming the three ears being so performed that a predetermined clearance exists between said surface of the second plate and the ears.

2. A method of assembling an ignition distributor of the kind specified comprising starting with a first annular plate having integral therewith three inwardly directed ears, the ears being spaced from the surface of the plate by a predetermined distance and being arranged so that anyone of the ears is on the opposite side of a diameter of the plate from the remaining ears, engaging with said first plate a second plate having three inwardly directed slots, said ears passing through said slots and mating parts on said first and second plates interengaging to mount the plates for relative angular movement, and, rotating the second plate relative to the first plate to displace the slots from their respective ears so that the ears retain the plates interengaged in an axial direction, said predetermined distance being such that a predetermined clearance exists between the ears and the surface of the second plate remote from the first plate, one of said first and second plates constituting a base plate while the other plate constitutes a timing plate and said one plate being arranged to be fixed to the casing of an ignition distributor while said other plate is arranged to support a contact breaker assembly.

3. A method of assembling an ignition distributor of the kind specified including the steps of engaging an annular timing plate with an annularbase plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three projections on a first plate of the pair of plates defined by the timing plate and the base plate engage the surface of the second plate, said projections being disposed on the first plate in such a manner that any one of the projections is on the opposite side of a diameter of the plate from the remaining projections, deforming three'ears formed on one plate of the first and second plates to engage the surface of the other plate of said first and second plates which surface is remote from the plate having the ears, the ears being so disposed that any one of the ears is on the opposite side of a diameter of a plate from the remaining ears, and rotating the first and second plates relative to one another so that the three projections enter respective apertures in the second plate, the dimensions of the apertures in the second plate being such that the first plate can move angularly relative to the second plate, and the first plate being movable axially relative to the second plate through a distance equal to the height of the projection.

4. A method of assembling an ignition distributor of the kind specified including the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three projections on a first plate of the pair of plates defined by the timing plate and the base plate project from the surface of the first plate, remote from the second plate, said projections being disposed on the first plate in such a manner that any one of the projections is on the opposite side of a diameter of the plate from the remaining projections, deforming three ears formed on the second plate to engage the surfaces of the three projections respectively and rotating the first and second plates relative to one another to displace the three projections angularly from the three ears so that the first plate is capable of movement axially relative to the second plate through a distance equal to the height of the projections.

5. A method as claimed in claim 3 wherein the projections formed on said first plate are formed by a half shearing operation on the first plate.

6. A method as claimed in claim 3 wherein said second plate constitutes, in use, the base plate and is arranged to be secured to a casing of the ignition distributor and said first plate constitutes, in use, the timing plate.

7. A method as claimed in claim 1 wherein the mating parts on the first and second plates comprise a cglindrical spigot integral with one of the plates, and t e wall of a circular hole in the other plate, said spigot being engaged in said hole.

8. A method as claimed in claim 4 wherein the projections formed on said first plate are formed by a half shearing operation on the first plate.

9. A method as claimed in claim 4 wherein said second plate constitutes, in use, the base plate and is arranged to be secured to a casing of the ignition distributor, and said first plate constitutes, in use, the timing plate.

10. A method as claimed in claim 2 wherein the mating parts on the first and second plates comprise a cylindrical spigot integral with one of the plates, and the wall of a circular hole in the other plate, said spigot being engaged in said hole. 

1. A method of assembling an ignition distributor of the kind specified including the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate, and deforming three ears formed on a first plate of the pair of plates defined by the timing plate and the base plate to overlie the surface of the second plate of said pair of plates remote from the first plate, said ears being disposed on said first plate so that any one of the ears is on the opposite side of a diameter of the plate from the remaining ears, said step of deforming the three ears being so performed that a predetermined clearance exists between said surface of the second plate and the ears.
 2. A method of assembling an ignition distributor of the kind specified comprising starting with a first annular plate having integral therewith three inwardly directed ears, the ears being spaced from the surface of the plate by a predeTermined distance and being arranged so that anyone of the ears is on the opposite side of a diameter of the plate from the remaining ears, engaging with said first plate a second plate having three inwardly directed slots, said ears passing through said slots and mating parts on said first and second plates interengaging to mount the plates for relative angular movement, and, rotating the second plate relative to the first plate to displace the slots from their respective ears so that the ears retain the plates interengaged in an axial direction, said predetermined distance being such that a predetermined clearance exists between the ears and the surface of the second plate remote from the first plate, one of said first and second plates constituting a base plate while the other plate constitutes a timing plate and said one plate being arranged to be fixed to the casing of an ignition distributor while said other plate is arranged to support a contact breaker assembly.
 3. A method of assembling an ignition distributor of the kind specified including the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three projections on a first plate of the pair of plates defined by the timing plate and the base plate engage the surface of the second plate, said projections being disposed on the first plate in such a manner that any one of the projections is on the opposite side of a diameter of the plate from the remaining projections, deforming three ears formed on one plate of the first and second plates to engage the surface of the other plate of said first and second plates which surface is remote from the plate having the ears, the ears being so disposed that any one of the ears is on the opposite side of a diameter of a plate from the remaining ears, and rotating the first and second plates relative to one another so that the three projections enter respective apertures in the second plate, the dimensions of the apertures in the second plate being such that the first plate can move angularly relative to the second plate, and the first plate being movable axially relative to the second plate through a distance equal to the height of the projection.
 4. A method of assembling an ignition distributor of the kind specified including the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three projections on a first plate of the pair of plates defined by the timing plate and the base plate project from the surface of the first plate, remote from the second plate, said projections being disposed on the first plate in such a manner that any one of the projections is on the opposite side of a diameter of the plate from the remaining projections, deforming three ears formed on the second plate to engage the surfaces of the three projections respectively and rotating the first and second plates relative to one another to displace the three projections angularly from the three ears so that the first plate is capable of movement axially relative to the second plate through a distance equal to the height of the projections.
 5. A method as claimed in claim 3 wherein the projections formed on said first plate are formed by a half shearing operation on the first plate.
 6. A method as claimed in claim 3 wherein said second plate constitutes, in use, the base plate and is arranged to be secured to a casing of the ignition distributor and said first plate constitutes, in use, the timing plate.
 7. A method as claimed in claim 1 wherein the mating parts on the first and second plates comprise a cylindrical spigot integral with one of the plates, and the wall of a circular hole in the other plate, said spigot being engaged in said hole.
 8. A method as claimed in claim 4 wherein the projections formed on said first plate are formed by a half sHearing operation on the first plate.
 9. A method as claimed in claim 4 wherein said second plate constitutes, in use, the base plate and is arranged to be secured to a casing of the ignition distributor, and said first plate constitutes, in use, the timing plate.
 10. A method as claimed in claim 2 wherein the mating parts on the first and second plates comprise a cylindrical spigot integral with one of the plates, and the wall of a circular hole in the other plate, said spigot being engaged in said hole. 